Residents wait to receive food aid distributed by the U.N. Relief and Works Agency (UNRWA) at the besieged al-Yarmouk camp, south of Damascus on January 31, 2014, in this handout picture made available to Reuters February 26, 2014 (Reuters)

Humanitarian aid for thousands of civilians trapped in a Palestinian-dominated area of the Syrian capital was halted as the district came under siege by Islamist rebels despite a long-negotiated truce.

The UN has voiced its concerns over the situation in the southern Damascus district of Yarmouk, where fighting erupted on Sunday. Around 20,000 people there are suffering from widespread starvation, malnutrition, and health problems, as they have been blocked from food, drinking water, and medical help for months now.

The UN "remains deeply concerned about the desperate humanitarian situation in Yarmouk, and the fact that increasing tensions and resort to armed force have disrupted its efforts to alleviate the desperate plight of civilians," UN spokesman in Damascus Chris Gunness said.

Speaking on behalf of the UN Relief and Works Agency (UNRWA), Gunness urged all parties to“immediately allow and facilitate the resumption of food distribution to civilians inside Yarmouk.”

On his Twitter account, Gunness said that “concerned parties” have reportedly held a ceasefire “for [the] last 48 hours” and continue “to negotiate ways to reduce tensions.”

The clashes, which are said to be the most serious violence to take place in the region for weeks, lasted until Monday morning and seriously undermined a tentative truce struck there in early January when limited food aid was allowed into Yarmouk, Reuters reported.

The truce took hold on February 10 in Yarmouk, after Al-Qaeda affiliate Al-Nusra Front withdrew fighters.

Yet on Sunday, Al-Nusra alleged that Syrian President Bashar Assad’s government forces and allies of the Popular Front for the Liberation of Palestine - General Command (PFLP-GC) broke the deal, AFP reported.

Al-Nusra claimed it had stood down for humanitarian reasons, but that “a very small number of food parcels” – much less than included in the agreement – had been distributed.

Al-Nusra reentered the camp on Sunday, activists confirmed.

"I was out filming and suddenly the shelling started. You should have seen the children: they were terrified," said activist Rami Al-Sayed.

"There are no civilians on the streets. Everyone's afraid and hiding in their houses because of the shelling and sniping," he continued.

Fighters of the Free Syrian Army, among other groups, were involved in Sunday’s clashes, according to an activist who uses the name Abu Akram, AP reported.

PFLP-GC blamed Al-Nusra for breaking the agreement when it reappeared at the camp.

"This morning, Al-Nusra Front returned once again to Yarmuk camp, disrupting the peace initiative whose aim was to address the tragedy of the hostage camp," said PFLP-GC spokesman Anwar Raja.

Al-Nusra is considered by Al-Qaeda to be its only legitimately affiliated group in Syria after repeated attempts by Al-Qaeda leader Ayman Al-Zawahiri to heal rifts between the Islamic State of Iraq and Levant (ISIL) and the more moderate Al-Nusra.

ISIL “is not a branch of the al-Qaeda group...does not have an organizational relationship with it and [Al-Qaeda] is not the group responsible for their actions,” Al-Qaeda’s General Command said in a statement one month ago.

South of Damascus, near rebel-dominated suburbs, Yarmouk became a valuable supply line for rebel fighters while attracting government artillery shelling that has destroyed large swaths of the district.

Activist Sayed told AFP that during the truce period, "the only medical relief that made it into Yarmouk was smuggled in, and in tiny amounts.”

Since January, UNRWA has given out over 7,500 food parcels in the camp, saying the amount was "a drop in the ocean compared with the rising tide of need.”

Months of shelling and fighting in and around Yarmouk between rebel groups and Assad loyalists have caused the camp’s population to go from 150,000 to 40,000. Around 18,000 Palestinians are among the residents.

SYRIA DIRECT: NEWS UPDATE 3-4-2014

* A pro-opposition citizen journalist in Yabroud denied reports that the Syrian army had gained complete control of the village of a-Sahel outside Yabroud in an interview with Syria Direct Tuesday, contrary to pro-regime media reports. On Monday, Hezbollah channel al-Manarannounced the Syrian army had recaptured complete control of A-Sahel, after rebels recaptured it last week, as well as an advance on the farms of a-Rima. The regime has advanced in a part of a-Sahel, but not seized entire control of it, the Yabroud-based citizen journalist said. “A-Sahel does not have great strategic importance compared to the hills surrounding it, and those remain under rebel control,” he added. Yabroud is the largest remaining rebel-held town in the Qalamoun mountain range, which stretches for some 80 km along Syria’s western border with Lebanon and overlooks the M-5 highway, which connects regime-controlled Damascus with the central city of Homs. The battle, which began last November, pits regime forces supported by Hezbollah troops against Free Syrian Army battalions, the Islamic Front, Jabhat a-Nusra and other rebel brigades.

* On Tuesday, multiple Islamic State in Iraq and a-Sham (ISIS) Twitter accounts announced that ISIS fighters have established a presence in Yarmouk Camp, using an Arabic hashtag called “ISIS liberates Yarmouk camp.” On Sunday, Jabhat a-Nusra re-entered the camp, citing the regime’s failure to abide by the terms of the truce, which include the entry of humanitarian aid. This comes as Syrian troops resume shelling of the camp, home to tens of thousands of Syrians and Palestinians, in response to Jabhat a-Nusra breaking a 19-day ceasefire. In 19 days of ceasefire, the Syrian Red Cross and Red Crescent and UNRWA had been able to deliver a limited amount of food and medical aid to Syrian and Palestinian residents of the camp, dozens of whom are reported to have starved to death in late January and early February as a result of a government-imposed blockade.

* Sheikh Moaz al-Khateeb rejected Tuesday a proposal that had circulated online suggesting he run for president of Syria against Bashar al-Assad in the upcoming June 2014. “I announce my rejection of participation in any fraudulent election, as participating in fraudulence is the greatest aid to the regime, falsity and corruption,” al-Khateeb wrote on his personal Facebook page. On Saturday, a group of anonymous activists launched a Facebook page titled, “The Popular Campaign to Nominate Moaz al-Khateeb as President of Syria Against Assad.” Though 70,000 Facebook users “liked” the page overnight, the campaign also launched a debate within opposition circles over whether running against al-Assad in so-called elections would only serve to further legitimize the Syrian president.

* U.N. Secretary General Ban Ki-Moon stressed Monday the urgency of relaunching the Syrian peace process, urging the regime in particular to return to Geneva with a more “constructive position.” The Geneva II talks broke down in January with regime representatives insisting on prioritizing the issue of “terrorism,” denoting opposition groups, which in turn maintain that putting in place a transitional government without President Bashar al-Assad is non-negotiable.

* The Islamic State in Iraq and Sham (ISIS) destroyed a Sufi shrine in the north central province of a-Raqqa Monday. ISIS justified its destruction of the shrine, dedicated to Abu al-Aeish, a respected sheikh in the north of the province, by declaring that nothing should “be worshipped other than God.” This came days after ISIS imposed restrictive rules on Christian citizens in a-Raqqa, promising the Christian minority protection provided that they accede to certain conditions. The statement demands that Christians pay the Islamic “jizya” tax, that they “not reveal their worship rituals outside the church,” not disparage Islam, and “submit to Islamicsharia in the state.”

Members of ISIS destroyed a Sufi shrine in a-Raqqa province Monday.

SYRIA DIRECT: NEWS UPDATE 3-3-2014

* A fresh wave of Syrian air raids struck the hills between the villages of a-Sahel and al-Falita on the outskirts of the town of Yabroud in the Qalamoun mountains Monday, with the Qalamoun Media Center reporting that Syrian warplanes had deployed cluster bombs over the area. Pro-government media said Syrian snipers had destroyed two rebel supply trucks and killed a number of “terrorists” in the Rima farms area, northeast of the town. Monday marked the twentieth day of a fresh regime-Hezbollah campaign to seize Yabroud, the largest-remaining rebel held town in the Qalamoun mountains, which contain a key stretch of the M5 highway connecting the Syrian capital with the central city of Homs.

* At least 12 government troops and members of the pro-Assad National Defense Force (NDF) militias were killed or injured Sunday in clashes with Jabhat a-Nusra and other rebel brigades south of the town of Mourik in eastern Hama province, the Syrian Observatory for Human Rights reported. Pro-government newspaper al-Watan, meanwhile, reported that government and NDF troops have established a “security perimeter” around the city of Mourik, preparing to storm the town and clear it of Jabhat a-Nusra “terrorists.” Mourik has been control by rebel groups, including Jabhat a-Nusra, since the beginning of February.

* The Islamic State in Iraq and a-Sham (ISIS) seized the three Kurdish villages of Shudud, Na’aman and Tel al-Bital near the town of al-Bab in northern Aleppo province Sunday, the Syrian Observatory for Human Rights reported. Pro-government newspaper al-Watan said regime troops had repelled a “terrorist” attempt to “attack the people of Aziza” in eastern Aleppo province, “destroying a number of their dens and gathering places.” Meanwhile, clashes between ISIS and Jabhat a-Nusra continue in the eastern provinces of al-Hasakeh and Deir e-Zor, east of ISIS’ strongholds in a-Raqqa province. On Sunday, Jabhat a-Nusra seized the town of al-Markadeh, the largest remaining ISIS-controlled village in al-Hasakeh province, pro-opposition Zaman al-Wasl reported.

* Four rebel fighters were killed and dozens injured in Syrian government shelling on the Damascus suburb of Adra on Sunday, pro-oppositon Smart News reported. Opposition groups including the Adra Local Coordination Committee (LCC) are claiming that the Syrian government used weapons containing poisonous gasses in the attack, though independent groups have yet to confirm the allegations and no video has surfaced depicting regime weapons. The regime “used chemicals in Adra,” the Adra LCC reported, “and there are a number of cases of asphyxiation.” Official government news agency SANA reported “dozens” of rebels had been killed. The Islamic Front’s Jaish al-Islam has controlled Adra since December 2013.

* Clashes renewed pitting Jabhat a-Nusra, Ajnad a-Sham and the FSA against government troops in the Yarmouk camp in Damascus on Sunday, breaking an unsteady, 19-day ceasefire that had allowed humanitarian organizations to deliver food and medical aid to starving citizens in the camp. Jabhat a-Nusra cited a list of five grievances as reasons to re-enter the camp, including the government’s failure to follow the guidelines of the truce in detaining dozens of civilians, allowing shabiha militants access to the camp, and showing reluctance to allow the delivery of aid. After months of government blockade, dozens of residents of the camp were reported to have starved to death in late January.

SYRIA DIRECT: NEWS UPDATE 3-02-2014

* Syrian warplanes continued raiding the rebel-held town of Yabroud in the Qalamoun mountains 75 kilometers north of Damascus on Sunday, the Syrian Observatory for Human Rights reported. On the ground, rebel groups are clashing with government forces supported by Hezbollah fighters as the Syrian regime seeks to advance into the last rebel-held town in the mountain range, considered the backbone of Syria’s western border with Lebanon. After weeks of clashes, pro-government newspaper al-Watan said Saturday the Syrian Arab Army had gained control of a al-Kuwaiti Hill which overlooksthe national highway between the government-held cities of Damascus and Homs. Rebel snipers from Yabroud have been targeting traffic on the road. Regime troops arrested 30 “terrorists” in operations on Saturday, Al-Watan reported, as it advanced in the town of al-Sahel, where rebels announced progress last week.

* Islamist rebels targetedthe village of Athimiat Saturday, at the entrance to the regime-controlled town of Khanaser in southern Aleppo province, the pro-opposition Sham News Network reported. Abu Firas, a citizen journalist in Aleppo province, announced rebels had destroyed two regime tanks and a store of artillery fire while claiming casualties of 40 regime troops when they ambushed a checkpoint in the village. In the city of Aleppo, pro-government al-Watan reported that government troops are just a few kilometers from rebel-encircled Aleppo Central Prison, in the midst of what the newspaper described as a “rapid” advance in the province. Government troops have been reporting advances from southeastern Aleppo into rebel-held eastern Aleppo since late January.

* As the June 2014 presidential elections in Syria approach, a group of Syrian activists launched a Facebook page Saturday titled, “The People’s Campaign to Nominate Moaz al-Khateeb for president of Syria Against al-Assad.” In less than one day, the page has received widespread attention on the social network, reaching more than 53,000 “likes.” Al-Khateeb is a former president of the opposition Syrian National Coalition, believed to be residing in Turkey. He resigned in March 2013, citing international meddling and frustration at a limited ability to bring about change, though he enjoyed popular support inside Syria. In December 2013, Syrian Deputy Foreign Minister Feisal al-Miqdad confirmed that “no one can prevent President Bashar al-Assad from running for re-election after the end of the current term in 2014." Al-Assad has never run opposed in an election, allegedly winning over 90 percent of the vote each time.

* Al-Qaeda affiliated rebel group Jabhat a-Nusra battalions gained control of a “large portion” of the town of al-Merkedeh in northeastern al-Hasakeh province after violent clashes with the Islamic State in Iraq and a-Sham, the Syrian Observatory for Human Rights reported. The Kurdish People’s Protection Units militias, ISIS, the Syrian government and rebel groups including Jabhat a-Nusra all control slices of the province and are vying for control of the majority-Kurdish province of al-Hasakeh. On Tuesday, Jabhat a-Nusra leader Abu Mohammed al-Jolani announced his fighters would confront ISIS after its suspected assassination of an al-Qaeda envoy and Ahrar a-Sham leader Abu Khaled a-Suri on Sunday, February 24th.